I am using IntelliJ Idea 2017.3 latest release in Ubuntu 2017.10 and shortcut Ctrl+Alt+Left/Right doesn\'t work.
Whereas from
I'm using ubuntu 16.04 LTS.
Go to System Settings -> Text Entry -> Keyboard Settings (bottom right of the screen).
On the keyboard dialog, click on Navigation tab. Then scroll down to "switch to workspace left" and select it and click backspace to disable it.
Your android studio shortcut should work now.